It sounds counter-intuitive, but that countries whose highly skilled citizens emigrate to seek their treasure in more developed countries are not ‘draining’ but actually ‘building’ the local economies where they were born, as long as the percentage doesn’t top 20%.

Why? A few points in the study: those who emigrate and ‘make it’ inspire others in their country to learn professions and skills (not all of them will emigrate); remittances sent back to the home country; the stability of remittances during times of crisis; the long-term prospects of remittances (cash coming into the country) that are not subject to shorter-term profit requirements as commercial investment may be.

The money that migrants send home is a huge source of income for poor countries. Recorded remittances to developing countries surged tenfold between 1990 and 2009, from $31 billion to $316 billion. Unrecorded ones — those envelopes stuffed with cash — nudge the total even higher. All told, remittances are more than double the amount of foreign aid sent to the developing world, and unlike aid, they are seldom stolen by grasping officials.